Initial commit

1 files changed, 38 insertions, 0 deletions

diff --git a/pkg/xtools/ranges/rgmerge.x b/pkg/xtools/ranges/rgmerge.x
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+++ b/pkg/xtools/ranges/rgmerge.x
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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<pkg/rg.h>
+
+# RG_MERGE -- Merge overlapping ranges in set of ordered ranges.
+
+procedure rg_merge (rg)
+
+pointer	rg				# Ranges
+
+int	new, old
+
+begin
+	# Error check the range pointer.
+
+	if (rg == NULL)
+	    call error (0, "Range descriptor undefined")
+	if (RG_NRGS(rg) == 0)
+	    return
+
+	# Eliminate overlapping ranges and count the number of new ranges.
+
+	new = 1
+	do old = 2, RG_NRGS(rg)
+	    if (RG_X1(rg, old) > RG_X2(rg, new) + 1) {
+		new = new + 1
+		RG_X1(rg, new) = RG_X1(rg, old)
+		RG_X2(rg, new) = RG_X2(rg, old)
+	    } else
+		RG_X2(rg, new) = max (RG_X2(rg, old), RG_X2(rg, new))
+
+	call realloc (rg, LEN_RG + 2 * new, TY_STRUCT)
+
+	RG_NPTS(rg) = 0
+	RG_NRGS(rg) = new
+	do new = 1, RG_NRGS(rg)
+	    RG_NPTS(rg) = RG_NPTS(rg) + RG_X2(rg, new) - RG_X1(rg, new) + 1
+end